A bridle such as a curb bridle allows the advanced rider to give finer aids on an appropriately trained horse. In the bridle of trained dressage horses, the curb typically comprises two bits—snaffle and curb—so that the rider must handle two pairs of reins simultaneously. The chin chain typically used currently in a curb bridle comprises multiple interlocking oval rings. A small round ring located in the middle of the chin chain, called a lip strap ring, was historically used for fastening the so-called lip strap (currently practically without significance). The lip strap for curb chin chains prevents the lower trees of the curb from getting too close to the mouth gap with loose reins and the horse being able to capture and hold these using his lips. The lip strap additionally ensures a correct effect of the chin chain at the correct point. The chin chain, which is always to be twisted to the right, is suspended in the right and left chin chain hooks of the curb, from the inside on the right side and from the outside on the left side. Its correct bending and/or flexibility is of significant influence on good bridling and effect.
The chin chains currently typically used for curbs are one-piece chains, to be twisted to the right, of the double round curb chain type. The curb chain is a chain type known in jewelry production, which is one of the so-called eye chains (or link chains). The basic type of the eye chain is the anchor chain, in which lying and standing eyes alternate. In contrast thereto, the curb chain comprises eyes or links uniformly lying flat, namely round or oval eyes or links twisted to the right. The twisting of the individual links causes the entire chain to have a rotational direction.
In detail, a chain twisted to the right comprises links which, in contrast to normal flat, round, or oval shaped chain links (as in an anchor chain, for example), are shaped in such a way that in the twisted state, they uniformly run together and/or interlock and thus allow the neighboring chain links not to stand perpendicularly to one another under tensile stress (as in the anchor chain, in which standing and lying links are situated alternately), but rather as flat as possible, in the ideal case in a line pressing against one another. A chain is thus obtained which has a flat surface, in the ideal case having a width corresponding to the width of the links, and which may adapt itself pressing flat and flexibly in all directions to a round surface, such as the chin of a horse. In jewelry production, one differentiates further between flat curb chains and round curb chains.
In the maximally flat state, which is thus maximally twisted to the right, i.e., in a state twisted maximally into itself in a right rotation, the chain may no longer be twisted further into itself to the right. I.e., the chain blocks further rotation to the right, i.e., it is closed in this direction. The chain opens in a left rotation, but leaves its maximum flat state. If the chain ends are fixed in the twisted state, as is the case when the chain is hung in the curb in the twisted state, the chain may no longer twist and maintains its flat, twisted state. Depending on how the links of the chain are shaped, the chain may also be overrotated beyond the maximum flat and twisted state, i.e., twisted further into itself. In the scope of the chain, twisted state means that the chain is maximally flat, i.e., is not overrotated if possible.
These chin chains, whose linkage of the individual links is oriented identically over the entire chain length, causes an uneven tension on both sides of the curb, however. Due to this varying force action, varying lever action on the curb rod in the mouth of the horse is achieved. More pressure is exerted on the interdental space and on the lips on the right than on the left. The uneven tension also causes the left chin chain hook to be drawn away from the mouth of the horse and the right chin chain hook to be drawn toward the mouth of the horse. Simultaneously, the effects on the mouth of the horse due to the differing lever effect on the curb rod—more pressure on the interdental space and lips on the right than on the left—are to be observed. This may result in tongue flaws, such as pushing out the tongue. Effects on the right corner of the mouth due to the tension inward on the right chin chain book are also to be observed. This is frequently to be observed from a lip hanging on one side on the right side of the mouth of the horse. In addition, this frequently results in injuries to the corner of the mouth.
WO 04/089809 discloses a two-part chin chain, which has a first chain element and a second chain element, the chain links each being linked opposite (turning out to the left and turning out to the right) in the first chain element and the second chain element. It is described that in this way a force which is exerted on the chin chain is dissipated uniformly onto the left side and the right side of the curb. A differing lever effect on one side, namely the increased pressure to the right on the curb rod, is thus precluded. In addition, the tension inward on the right chin chain hook is thus compensated for or canceled out. This chin chain advantageously counteracts a lip hanging on one side, injuries on the corner of the mouth, and tongue flaws.
The chain described has the disadvantage that it is to be used in connection with a commercially available rubber underlay, into which the twisted chain is inserted. Only in this way may be twisted and flat state be maintained and/or twisting of the individual chain links be suppressed, and thus also injury to the horse by the twisted chain links may be avoided.
As described above, commercially available chains which only have one rotational direction may not twist opposite thereto when they are hung twisted. The chain is locked by the suspension. In two-part chains having right and left rotation, such locking is lacking, because the chain is no longer fixed by the rotational direction reversal, it may twist even when its ends are fixed.
As indicated in FIG. 1, the right chain element (4) is open for one rotational direction and blocked or closed for the opposite direction, and the left chain element (2) is open and blocked or closed precisely in reverse. The chain twists easily when it is moved or shaken, or overturned entirely when it is prevented from twisting in regard to its individual links by a rubber underlay.